Variable Angle Transmission Accessory

This Variable Angle Transmission Accessory is excellent for examining thick samples and optical coatings thereon at any angle using transmission spectroscopy.  When light impinges on a thick sample at an angle, the light reflects from both surfaces of the sample. The transmitted light is parallel to the incident light but slightly shifted. The measured transmittance is altered by this misalignment of the beam. The Variable Angle Transmission Accessory eliminates this by allowing a sample and a blank to be placed in the beam at the same angle but in opposing directions.  Using a blank which matches the sample in thickness and refractive index shifts  the transmitted beam back to the original position.  This accessory incorporates a holder for an optional polarizer.  For optimum performance with inherently polarized beams, the accessory can be rotated 90° around the beam axis.  This accessory is designed for FT-IR or UV-Vis transmission studies of samples up to 6 mm thick and up to 10 mm thick with its included thick sample holder.

Features & Includes


  • Accommodates samples up to 6mm thick and at least 25mm high with the standard sample holder.
  • Secures both sample and matched blank for optical thickness compensation.
  • Fully rotatable for incident angles from 0° and up to 90°.
  • Angular scale from 0° to 90° marked in 1° increments.
  • Maximum angle achievable depends on sample thickness and width.
  • Useful for angles up to 60° with 6mm thick, 43mm wide samples. Wider samples can reach a higher maximum angle.
  • Mountable in two positions to maximize performance with inherently polarized incident radiation.
  • Includes sample holder set for use with samples up to 10mm thick.
  • Compatible with both FT-IR and UV-VIS polarizers.

Related Accessories


Model No. Name
VAT2-S10 Thick Sample (6-10mm) Holder for VAT2

Technical Info

For assistance with your order, please contact customer service at 1-800-248-3847


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